Chia seed extract and related method of manufacture

ABSTRACT

Ethanolic chia ( Salvia hispanica ) seed extracts are provided in a system including one or more polyols and at least one hydrophobic compound that solubilize hydrophobic and slightly hydrophilic fractions of the extracts. The polyol can be pentylene glycol. The at least one hydrophobic compound can be a light oil or an ester including, but not limited to, glyceryl caprylate, glyceryl trioctanoate, isodecyl neopentanoate, isononyl isononanoate, isopropyl myristate, phenethyl benzoate, propylene glycol dicaprylate/dicaprate, propylene glycol dioctanoate and combinations thereof. The system or solution can form a cosmetic composition which is highly stable. A method for preparing the composition also is provided.

BACKGROUND OF THE INVENTION

The present invention relates to solubilized chia seed extracts and moreparticularly, to the use of polyols, light oils and/or esters forsolubilization of chia seed extracts.

Common chia seed extracts include oils extracted from the seeds of chiaby pressing or by solvent extraction. Currently, there are four categoryentries listed in the Cosmetic, Toiletry and Fragrance Association(“CTFA”) Online Ingredient Database under the name of Chia (Salviahispanica) seed for cosmetic applications. These categories include: (1)chia (Salvia hispanica) seeds or seed powder, used as abrasives; (2)chia seed oil, used as occlusive skin conditioning agents; (3) chia seedCO₂ extract, (with no solvent/diluent, CO₂ is a non-polar solvent so dueto its selectivity, CO₂ extraction usually results in a specifichydrophobic fraction of chia seeds); and (4) chia seed extract solution.There are two water soluble blends of chia seed extract including: HPChia Seed Gel, manufactured by Morechem Co., Ltd. of Metro Manila,Philippines, which is a mixture of water, butylene glycol and Salviahispanica seed extract; and Chia Extract, which is manufactured byCarrubba, Inc. of Milford, Conn., USA, and which is a mixture ofglycerin, water, and Salvia hispanica seed extract.

There are a variety of U.S. patents that individually relate to chiaseed oil, however, none known to the Applicants show or even contemplatea solubilization or stabilization process that incorporates both polyolsand hydrophobic light oils and/or esters. For example, some patentsrelate to the following: a skin care composition containing chia seedoil for moisturization and appearance of skin; manufacturing conditionsof producing chia seed oil containing polyunsaturated fatty acids;cosmetic compositions containing fatty acid triglyceride mixtures fromvarious seeds including chia seeds; use of chia oil in cosmetic anddermatologic compositions containing salicylic acid; use of chia oil asemollient in skin care applications; use of chia oil as one oilycomponent in a film-forming composition for skin care applications; oruse of chia oil as an oily component in an antioxidant composition.

SUMMARY OF THE INVENTION

A cosmetic composition including a solubilized chia seed extract and amethod of manufacturing the same are provided. In one embodiment, asolubilized chia (Salvia hispanica) seed extract composition includes:an ethanolic chia seed extract; at least one polyol; at least onehydrophobic compound selected from the group consisting of esters, lightoils and combinations thereof.

In another embodiment, the method includes extracting hydrophobic andslightly hydrophilic components from chia (Salvia hispanica) seeds andstabilizing them in a dual-solvent system to achieve a clear andthermodynamically stable solution suitable for use in cosmeticapplications, for example, in topical cosmetic compositions used forskin lightening.

In still another embodiment, a method of solubilizing an ethanolic chia(Salvia hispanica) seed extract includes: providing an ethanolic chiaseed extract; and admixing the chia seed extract in at least one polyol,and at least one hydrophobic compound selected from the group consistingof esters, light oils and combinations thereof, to form a solubilizedchia extract.

In yet another embodiment, a composition is provided that is formed bythe solubilization steps: providing an ethanolic chia (Salvia hispanica)seed extract; and admixing the chia seed extract in at least one polyoland at least one hydrophobic compound selected from the group consistingof esters, light oils and combinations thereof.

In even another embodiment, the polyol is pentylene glycol, and thehydrophobic compound can be selected from the group consisting ofglyceryl caprylate, glyceryl trioctanoate, isodecyl neopentanoate,isononyl isononanoate, isopropyl myristate, phenethyl benzoate,propylene glycol dicaprylate/dicaprate, propylene glycol dioctanoate andcombinations thereof.

In a further embodiment, the hydrophobic compound is a blend of C₁₂-C₁₅alkyl benzoate, dipropylene glycol dibenzoate, and PPG-15 stearyl etherbenzoate.

In still a further embodiment, the ratio of pentylene glycol to thehydrophobic compound is from 4:1 to 3:10.

In yet a further embodiment, the ratio of pentylene glycol to thehydrophobic compound is 12:7.

In even a further embodiment, the solubilized chia extract comprisespentylene glycol, isononyl isononanoate, and chia seed extract. Thesolubilized chia extract can include about 23% to about 80% pentyleneglycol, about 20% to about 77% isononyl isononanoate, and about 0.5% toabout 20% chia seed extract or optionally 60% pentylene glycol, 35%isononyl isononanoate and 5% chia seed extract.

The current embodiments can efficiently extract hydrophobic and slightlyhydrophilic components from chia seeds, and stabilize them in adual-solvent system to achieve a clear and thermodynamically stablesolution suitable for use in cosmetic applications.

These and other objects, advantages and features of the currentembodiments will be more readily understood and appreciated by referenceto the detailed description of the current embodiments and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a process flowchart for preparing a chia seed extract solutionaccording to a current embodiment;

FIG. 2 is an image of a chia seed extract concentrate beforesolubilization and a chia seed extract after solubilization in adual-solvent system of the current embodiment;

FIG. 3 is a table illustrating a solvent system selection of polyols foruse in the current embodiment;

FIG. 4 is a table illustrating a solvent system selection of light oilsor esters for use in the current embodiment;

FIG. 5 is a table illustrating the miscibility of a polyol and anoil/ester in a dual-solvent system of the current embodiment; and

FIG. 6 is a table illustrating the solubility of chia seed extractconcentrate in dual-solvent systems of the current embodiment.

DETAILED DESCRIPTION OF THE CURRENT EMBODIMENTS

A current embodiment is described herein in connection with thepreparation and use of chia seed extracts. Although described inconnection with cosmetic applications, the current embodiments can beused in a variety of other applications.

Chia and its extracts have a variety of beneficial cosmetic uses andactivities. For example, chia seed extracts have been demonstrated tohave melanin inhibition activity via in vitro efficacy studies, asillustrated in U.S. Patent Publication 2011/0212201 to Rana et al, whichis hereby incorporated herein by reference in its entirety. Of course,the extracts of the current embodiments can be used in connection withother beneficial activities.

Certain terms herein have certain meanings unless otherwise specified.For example, the term “chia” as used herein refers to Salvia hispanica.The term “cosmetic” as used herein refers to any preparation designed tobeautify, alter the appearance, provide a benefit to a body surfaceand/or tissue to which it is applied, or to provide a benefit to thesubject to which it is applied. Cosmetic can include dermatological andneutraceutical compositions. The term “topical” as used herein refers tobeing applied directly to the skin. The term “hydrophilic” as usedherein refers to being capable of associating with a solution by forminghydrogen bonds with water or other hydrophilic molecules or compounds inthe solution, such as alcohols. The terms “hydrophobic” as used hereinrefers to having little or no affinity for water, or incapable ofdissolving to any appreciable extent in water or hydrophilic compound ormolecules, for example, alcohols. The term “slightly hydrophilic” refersto a substance that has both hydrophilic and hydrophobic/lipophilicproperties, for example, an amphiphilic substance where such a substancecan be temporarily solubilized in an oil-based solution by formingrelatively unstable bonds or associations with hydrophobic compounds ormolecules, but within a short time (e.g., 5 minutes to 5 weeks or more)the substance precipitates out from the solution.

Applicants have discovered that the extraction of whole seeds of chia,with ethanol being the extraction solvent, is complicated by theresulting fractures of the extract. Specifically, both hydrophobicfractions and slightly hydrophilic fractions are extracted from wholeseeds of chia. The hydrophobic fraction of the chia seed extract hereinincludes fats, linolenic acid, linoleic acid, oleic acid, palmitic acid,stearic acid, ferulic acid, and other oil soluble components. Theslightly hydrophilic fraction of the chia seed extract includes avariety of alcohol soluble proteins and alcohol soluble polypeptides.

The coexistence of the hydrophobic and the slightly hydrophilicfractions in the ethanolic extract of chia seed presents practicalchallenges during extraction and formulation stages. For example, theslightly hydrophilic fraction separates from the hydrophobic fraction toform a sticky precipitate in the concentration process after ethanolicextraction. This sticky precipitate sticks to any surface that itcontacts when the ethanol is gradually removed, making the slightlyhydrophilic fraction less available in final product, which can diminishits intended use and activity. Moreover, in final product, the slightlyhydrophilic fraction continues to precipitate gradually over time, e.g.,5 minutes to 5 weeks or more, which leaves a layer of sticky precipitateat the bottom of the associated container. In addition, this precipitateis exceedingly difficult to re-dissolve at the time when the product isto be used in a manufacturing environment. As a result, the slightlyhydrophilic fraction is less available, or in some cases unavailable,for use in the final product. Where the final product is a topicalcosmetic, this can result in the beneficial slightly hydrophilicfraction of chia being less available, or unavailable, for its intendedactivity on the skin or other application surface. These technicalchallenges have made such ethanolic extracts of chia impractical for usein most cosmetic applications.

The current embodiments overcome the above challenges in at least twoways. First, the methods extract both hydrophobic and slightlyhydrophilic fractions from chia seeds using ethanol as extractingsolvent. The resultant extract provides melanin inhibition efficacy viacell-based in vitro studies. Second, the methods of the currentembodiments solubilize and stabilize both the hydrophobic and theslightly hydrophilic fractions in the final extract, which is criticalto a commercially viable material suitable for cosmetic applications.Specifically, the dual-solvent system of the current embodimentsdissolves both hydrophobic fraction and the sticky, slightly hydrophilicfraction to form a clear (but slightly yellow in color) solution ofextract which is thermodynamically stable at room temperature, and whichis resistant to precipitation of the slightly hydrophilic fraction ofchia. This dual-solvent system produces a chia seed extract that issuitable for cosmetic and other applications.

The composition of the current embodiment includes chia seed extract,which extract can be obtained from a single ethanolic solventextraction. When extracted, the chia seed can include multiplefractions, but primarily includes a hydrophobic (e.g., lipophilic or oilsoluble) fraction and a slightly hydrophilic fraction. It is believedthat the single ethanolic extraction of the current embodiment preservesthe activity of the fractions, particularly when the extract is used incosmetic applications.

In the current embodiment, the resulting solubilized chia seed extractsystem, also referred to as a solution herein, can include the abovementioned chia seed extract, a polyol of the type described herein andan ester and/or light oil as described herein. The chia seed extract canbe present in an optional amount of about 0.5% to about 20%, or afurther optional amount of about 2% to about 10% by weight (wt/wt) ofthe solubilized chia seed extract system. The polyol can be present inan optional amount of about 23% to about 80%, or a further optionalamount of about 40% to about 70% by weight (wt/wt) of the solubilizedchia seed extract system. The ester and/or light oil can be present inan optional amount of about 20% to about 77%, and a further optionalamount of about 28% to about 50% by weight (wt/wt) of the solubilizedchia seed extract system.

As mentioned above, the solubilized chia seed extract system can includeleftover ethanol from an earlier extraction procedure. That ethanollevel can be relatively low to reduce the effect of the alcohol on theskin of a user should the solubilized chia seed extract system befurther incorporated into a cosmetic composition. For example, theethanol in the solubilized chia seed extract system can be present in anoptional amount of about 0.25% to about 10% by weight (wt/wt) of thesolubilized chia seed extract system, or a further optional amount ofabout 1% to about 5% by weight (wt/wt) of the solubilized chia seedextract system, and an even further optional amount of about 2.5% byweight (wt/wt) of the solubilized chia seed extract system.

Other features of the current embodiments will become apparent in thecourse of the following descriptions of exemplary embodiments, which aregiven for illustration of the current embodiments, and are not intendedto be limiting thereof. In the following examples, all amounts are givenin percent by weight of the solubilized chia seed extract system orsolution, that forms the resultant cosmetic composition, unlessotherwise specified.

EXAMPLE 1

A solubilized chia seed extract system was obtained from the whole chiaseeds. The method for obtaining the solubilized chia seed extract systemincluded the following steps, which are generally illustrated in theflow chart of FIG. 1.

(1) The chia seeds were cleaned and dried. Suitable seeds are Salviahispanica seeds from Nutrilite Farm of El Petecal, Mexico.

(2) The chia seeds were milled with a ball or hammer mill to breakand/or fragment the seed material into smaller pieces for extraction.

(3) The milled chia seeds were added to ethanol in an extractioncontainer and extract with 93-95% ethanol at 120° F. (49° C.) for 3hours, which included a 1 hour hold time, and 2 hours of extraction withagitation. The ratio of ground chia seed:ethanol was 1:10.

(4) The content from the extraction container was filtered through aLIQUATEX Separator fitted with a 325 mesh screen. The separator iscommercially available from Rotex, Global, LLC located in Cincinnati,Ohio.

(4A) The liquid filtrate was collected and then underwent amicrofiltration step to remove fine, insoluble particulates. Themicrofiltration unit was equipped with a FP200 (200,000 MolecularWeight) PVDF (polyvinylidene fluoride) tubular membrane. The feedpressure was set at 8-10 bars and the product temperature was 70-80° F.The unit and membranes are commercially available from PCI MembraneSystems located in Hamilton, Ohio. The retentates from these twofiltration operations were recovered as by-products and optionallyrecycled, used as energy or discarded as waste, as indicated in FIG. 1.

(5) The permeate from the microfiltration step was collected andtransferred to an evaporator (such as Turbafilm or CentrithermEvaporators) to remove the extraction solvent (ethanol) from the extractsolution. Suitable evaporators include a Turba-Film evaporator,available from LCI Corp. of Charlotte, N.C., or a Centrithermevaporator, available from FT Industrial Pty. Ltd of Griffith,Australia. Optionally, the ethanol was recovered for re-use or otheruse. This operation results in an ethanolic chia seed extractconcentrate having an ethanol content controlled at optionally less than30%, further optionally, less than 20%, by percent weight of theethanolic extract concentrate. Generally, due to their limited solvency,the hydrophobic and slightly hydrophilic fractions of chia extract weresuspended in the extract concentrate to yield a yellowish brown, opaque,and slightly viscous material 104, shown in FIG. 2. This concentratecontained about 50-80% non-volatiles and a suspension of fine particles.

(6) The chia seed extract concentrate was mixed with a dual-solventsystem, pentylene glycol and isononyl isononanoate at room temperature77° F. (25° C.) to obtain a completely dissolved, clear, thin and stableliquid of chia seed extract solution 102, shown in FIG. 2. The resultantcomposition of this solubilization/stabilization process was asolubilized chia seed extract system or a solution including pentyleneglycol: 60%; isononyl isononanoate: 35%; and chia seed extractconcentrate: 5%.

In other embodiments beyond the above example, the solubilized chia seedextract system, also referred to as a solubilized and stabilized chiaextract composition herein, can include: optionally, about 50% to about70% polyols and further optionally, about 55% to about 65% polyols;optionally, about 25% to about 45% esters and/or light oils and furtheroptionally, about 30% to about 40% ester and/or light oils; andoptionally, about 1% to about 15% chia seed extract concentrate andfurther optionally about 2% to about 10% chia seed extract concentrate.

The solubilization and stabilization step is considered as the key stepin the current embodiment. Due to the unique composition and extractionprocess, both hydrophobic fractions and slightly hydrophilic fractionsin chia seeds are extracted out in the ethanol solution. Moreover, bothof these fractions are solubilized within the system, so that theslightly hydrophilic fractions do not precipitate out and/or separatefrom the solution. In turn, both fractions remain available for use in acosmetic composition, and both fractions generally remain homogeneouslymixed throughout the composition. Thus, when the composition (or somefinal cosmetic formulation in which the composition is included) is, forexample, topically applied to skin, both the hydrophobic and slightlyhydrophilic fractions are present in the amount of substance applied sothat their activities can be imported to the skin.

Applicants have discovered that another way to maintain solubilizationof the hydrophobic and slightly hydrophilic fractions in chia seeds isto have very high ethanol content, for example 80% ethanol; however,this poses flammability concerns and makes a commercial applicationelement nearly impossible. Reducing ethanol levels, however, waspresumably thought by Applicants to likely result in solubilityconcerns, based on the slightly hydrophilic fraction in the extractseparating from the solution at low ethanol levels (e.g., less than 60%ethanol), and forming a sticky layer of precipitate which will stick toany surfaces that it contacts. Applicants determined that thissolubility issue made it extremely difficult to recover the activefractions and adequately dissolve the active fractions in a cosmetic orother formulation, without the benefit of the current embodiment.

The efficacy of the present dual-solvent system was confirmed afterextensive solubility studies. Applicants specifically investigatedisononyl isononanoate, which is a light ester, to dissolve lipid solublematerials, and pentylene glycol, which is a polyol that is easilymiscible with aqueous solutions, to dissolve hydrophilic and slightlyhydrophilic materials. These two solvents are miscible at a wide rangeof ratios and, as the Applicants discovered, the resulting solution hasthe unexpected ability to dissolve both the hydrophobic and the slightlyhydrophilic fractions in chia seed extracts, and maintain thesefractions—and in particular, the slightly hydrophilic fraction in thesolution—without that slightly hydrophilic fraction precipitating out,after 5 minutes to 5+ days, or even after a significant storage periodof at least six months, or even a year or more, at temperatures rangingfrom about 65° F. to about 80° F.

Again, the resulting solubilized chia seed extract solution 102 is shownin FIG. 2 together with the chia seed extract concentrate 104 before itwas solubilized. The resulting solubilized chia seed extract solution102 is a thin, clear, one-phase, light-yellow liquid which isthermodynamically stable at room temperature storage conditions, forexample about 65° F. to about 80° F.

In making the present discovery, many polyols and light esters wereevaluated, individually and in combination; however, it was discoveredthat only a limited number of combinations of polyols and light estershave the ability to solubilize the unique fractions in the chia seedextract. FIGS. 3-6 illustrate the solubilization of ethanolic chia seedextracts using various solvents and their combinations. Moreparticularly, the detailed and self explanatory test results onsolubility of single solvent, miscibility of polyol and light oil/esterin a dual-solvent system, as well as the solubility of chia seed extractconcentrate in various dual-solvent systems are shown in FIGS. 3-6. Ofthe polyols tested (glycerin, glycereth-26, propylene glycol, butyleneglycol, pentylene glycol, hexylene glycol and isoprene glycol), onlypentylene glycol showed the ability to form a dual-solvent system with alimited number of light esters that have the ability to solubilize thecomplex fractions extracted from chia seeds. Of the light oils/esterstested, there are multiple esters able to form a dual-solvent systemwith pentylene glycol to adequately dissolve the complex fractionsextracted from chia seed. Those light oils/esters include: acommercially available blend of C₁₂-C₁₅ alkyl benzoate and dipropyleneglycol dibenzoate and PPG-15 stearyl ether benzoate; glyceryl caprylate;glyceryl trioctanoate; isodecyl neopentanoate; isononyl isononanoate;isopropyl myristate; phenethyl benzoate; propylene glycoldicaprylate/dicaprate; and/or propylene glycol dioctanoate.

Based on the Applicants' discovery, it was determined that suitableratios of polyols to the light oils/esters above was from 4:1 to 3:10.This range of ratios was particularly relevant where the polyol waspentylene glycol and the ester was isononyl isononanoate. Oneparticularly suitable ratio of pentylene glycol to isononyl isononanoatewas 12:7, at which the polyols and light oils/esters solubilized verywell the chia seed extract concentrate fractions, e.g., both thehydrophobic and slightly hydrophobic fractions, in the chia seed extractsystem or solution.

The resulting solubilized chia seed extract system or solution is wellsuited for use as a cosmetic composition. The system can be used byitself, or it can be included with other ingredients such as carriers,permeation enhancers and other extracts in a final product cosmeticformulation.

The above descriptions are those of the preferred embodiments of theinvention. Various alterations and changes can be made without departingfrom the spirit and broader aspects of the invention as defined in theappended claims, which are to be interpreted in accordance with theprinciples of patent law including the doctrine of equivalents. Anyreferences to claim elements in the singular, for example, using thearticles “a,” “an,” “the,” or “said,” is not to be construed as limitingthe element to the singular. Any reference to claim elements as “atleast one of X, Y and Z” is meant to include any one of X, Y or Zindividually, and any combination of X, Y and Z, for example, X, Y, Z;X, Y; X, Z; and Y, Z.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:
 1. A method of preparing acosmetic composition comprising: providing an ethanolic chia (Salviahispanica) seed extract, the extract including less than 30% ethanol byweight of the ethanolic chia seed extract, a chia seed hydrophobicfraction, and a chia seed slightly hydrophilic fraction; and admixingthe ethanolic chia (Salvia hispanica) seed extract with a polyol and atleast one hydrophobic compound to form a solubilized chia extractcosmetic composition, wherein the polyol solubilizes a first portion ofthe chia seed hydrophobic fraction and solubilizes the chia seedslightly hydrophilic fraction, wherein the at least one hydrophobiccompound is at least one of an ester and a light oil, wherein thehydrophobic compound solubilizes a second portion of the chia seedhydrophobic fraction, wherein the solubilized chia seed extract cosmeticcomposition comprises 60% pentylene glycol, 35% isononyl isononanoate,and 5% ethanolic chia (Salvia hispanica) seed extract by percent weightof the solubilized chia seed extract cosmetic composition.
 2. The methodof claim 1 wherein the hydrophobic compound includes the isononylisononanoate and at least one of glyceryl caprylate, glyceryltrioctanoate, isodecyl neopentanoate, isopropyl myristate, phenethylbenzoate, propylene glycol dicaprylate/dicaprate, propylene glycoldioctanoate and combinations thereof.
 3. The method of claim 1 whereinthe hydrophobic compound includes isononyl isononanoate blended with atleast one of C₁₂-C₁₅ alkyl benzoate, dipropylene glycol dibenzoate andPPG-15 stearyl ether benzoate and combinations thereof.
 4. The method ofclaim 1 wherein the polyol is pentylene glycol and the hydrophobiccompound is isononyl isononanoate.
 5. The composition of claim 1 whereinthe solubilized chia seed extract cosmetic composition is in the form ofa substantially clear, one-phase liquid which is thermodynamicallystable when stored between 65° F. and 80° F. for a period of at leastsix months.
 6. A method of preparing a cosmetic composition comprising:providing an ethanolic chia (Salvia hispanica) seed extract including achia seed hydrophobic fraction and a chia seed slightly hydrophobicfraction; and admixing the ethanolic chia seed extract with a dualsolvent system to form a solubilized chia seed extract cosmeticcomposition, the dual solvent system including at least one polyol thatsolubilizes the chia seed hydrophobic fraction and the chia seedslightly hydrophobic fraction, the dual solvent system including atleast one of an ester and a light oil that solubilizes the chia seedhydrophobic fraction, wherein the polyol is pentylene glycol, whereinthe at least one of an ester and a light oil is isononyl isononanoate,and wherein the ratio between pentylene glycol and the isononylisononanoate is 12:7.
 7. The method of claim 6 wherein the solubilizedchia seed extract cosmetic composition comprises about 23% to about 80%of the polyol and about 20% to about 77% of the hydrophobic compound bypercent weight of the solubilized chia seed extract cosmeticcomposition.
 8. The method of claim 6 wherein the solubilized chia seedextract cosmetic composition includes less than 7% ethanol by percentweight of the solubilized chia seed extract cosmetic composition.
 9. Thecomposition of claim 6 further comprising at least one of glycerylcaprylate, glyceryl trioctanoate, isodecyl neopentanoate, isononylisononanoate, isopropyl myristate, phenethyl benzoate, propylene glycoldicaprylate/dicaprate, propylene glycol dioctanoate, and combinationsthereof.
 10. The composition of claim 6 wherein the solubilized chiaseed extract cosmetic composition is in the form of a substantiallyclear, one-phase liquid which is thermodynamically stable when storedbetween 65° F. and 80° F. for a period of at least six months.